Chapter 1: New Ponds
A bank of thriving lupines at my pond resulted from a chance mix of experimental gardening and just the right soil and southern exposure.
Paradoxical as it may sound, there is such a thing as pond landscaping. You may have heard it called pondscaping, although that’s a term usually reserved for water gardens and pools, especially those incorporating the rich variety of aquatic plants that can be used in small liner ponds. The large natural or earth ponds I’m concerned with make a bigger statement, and the land around them offers space for meadow flowers and grasses, perennial flowers, bird attraction, shrubs, and shade trees; paths, stonework, bridges, docks, and outbuildings; and even the sky.
“Less is more” is the favored approach to large-pond landscaping for many of my clients. The gentle arc of a dam, naturally curving shoreline, and liquid mirror reflecting the sky, clouds, and trees contribute to the tranquil natural effect many pond owners seek.
Earth ponds may benefit from aquatic plantings, but many pond owners are careful to limit invasive species, such as cattails, reeds, water lilies, and rushes, to edges and bays, making sure they don’t overpopulate the main pond basin.
This excavated pond, as viewed from the house, was built in a wet hollow and relies on groundwater for its supply. The owner preserved trees to establish a foreground perspective and to create two distinct habitats, domestic and natural. Screening can also encourage wildlife.
Some pond owners are reluctant to add any plants at all to the basin or shore of their ponds for fear of the damage invasive plants wreak, including choking all other plants out, root damage to the embankment, or attracting animal pests like beavers and muskrats. Some wetland designers advocate a hands-off strategy that allows native plants to populate the shores naturally, eliminating the expense and possible regret of importing plants unsuited to the conditions. Alas, this kind of laissez-faire approach rules out the sort of plant experimentation that can lead to attractive, manageable, and pleasantly surprising results.
Ponds intended for swimming, skating, and raising fish depend on good water quality, which can be quickly spoiled by invasive aquatic plants, or algal blooms triggered by plant nutrients, or fish food and fish waste. In pond landscaping, a careful balancing act is required.
Bottom line: building and maintaining an earth pond can be an act of landscaping in itself. After all, what’s the difference between planting a tree and watching it grow and digging a pond and watching it grow? Much like a plant, a pond changes with age, weather, and the seasons. Leave it alone, and you may be perfectly content with Mother Nature’s plan. On the other hand, like an orchard or a garden, a pond can benefit from smart, creative design, planting, and periodic maintenance to make it attractive and healthy. We’ll look at both strategies throughout this book.
First, let’s look at the two basic pond types for a fundamental sense of their landscape characteristics. Whether you build a pond from scratch or buy property with an existing pond, you’ll be dealing with either an excavated pond or an embankment pond.
The dam used to create this embankment pond doubles as the driveway to the house. Aesthetically and environmentally, a gravel surface beats asphalt.
Excavated ponds are built by digging out a basin on relatively flat, low-lying wet terrain and letting groundwater do the rest. Embankment ponds are created by building an earth/clay fill or a concrete dam on the downhill side of a slope or stream to hold water back. Conveniently enough, the embankment is often constructed with the earth excavated during creation of the basin.
Excavated ponds are generally easier to build and landscape than embankment ponds (wetland permits notwithstanding). In an excavated pond the groundwater flow is typically more predictable and reliable than the small surface streams of an embankment pond. Simple economical and efficient earthen spillways are commonly used, and they can be designed to include natural effects like stone bedding, waterfalls, and aquatic plants. There are few structural liabilities to planting trees on the shore of an excavated pond; not so an embankment pond. Trees and shrubs sited around an excavated pond create a narrative arc of seasonal colors and forms, from spring blossoms through autumn foliage. On the other hand, wetland sites and aquatic plantings make ponds vulnerable to water-weed infestations and beaver or muskrat damage.
Extensive plantings around this excavated pond provide shade, animal habitat, and attractive surroundings, as well as privacy screening from a nearby road.
Planting trees and shrubs on a pond’s embankment, however, is a bad idea, because roots can lead to leakage and erosion. In addition, pond embankment construction compacts the soil, creating tough conditions for many plants. Still, it is possible to plant shallow-rooted shrubs and plants on a pond embankment, especially along the outside edge in specially prepared soil. The broader the embankment top, the better the chance of planting far enough away from the water’s edge to avoid problems with root damage and runoff nutrients.
When properly handled, the earthen terrace along the top of an embankment can be a dammed pond’s chief landscape asset. It can serve as shoreline beach area, picnic ground, or simply a comfortable observation area for taking in the pond and its upstream landscape, or, with an about-face, a valley view below. Once you’re acquainted with the two earth pond types, you can intelligently evaluate pond sites (or existing ponds) for their landscaping potential.